Pedosphere 17(1): 117--123, 2007
ISSN 1002-0160/CN 32-1315/P
©2007 Soil Science Society of China
Published by Elsevier B.V. and Science Press
| Effect of selected organic acids on cadmium sorption by variable- and permanent-charge soils |
HU Hong-Qing1 , LIU Hua-Liang1, HE Ji-Zheng1,2 and HUANG Qiao-Yun1 |
1 Key Laboratory of Subtropical Agriculture Resource and Environment, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070 (China). E-mail: hqhu@maxl.hzau.edu.cn
2 Research Center for Eco-Environment, Chinese Academy of Sciences, Beijing 100085 (China) |
| ABSTRACT |
| Batch equilibrium experiments were conducted to investigate cadmium (Cd) sorption by two permanent-charge soils, a yellow-cinnamon soil and a yellow-brown soil, and two variable-charge soils, a red soil and a latosol, with addition of selected organic acids (acetate, tartrate, and citrate). Results showed that with an increase in acetate concentrations from 0 to 3.0 mmol L-1, Cd sorption percentage by the yellow-cinnamon soil, the yellow-brown soil, and the latosol decreased. The sorption percentage of Cd by the yellow-cinnamon soil and generally the yellow-brown soil (permanent-charge soils) decreased with an increase in tartrate concentration, but increased at low tartrate concentrations for the red soil and the latosol. Curves of percentage of Cd sorption for citrate were similar to those for tartrate. For the variable-charge soils with tartrate and citrate, there were obvious peaks in Cd sorption percentage. These peaks, where organic acids had maximum influence, changed with soil type, and were at a higher organic acid concentration for the variable-charge soils than for the permanent charge soils. Addition of cadmium after tartrate adsorption resulted in higher sorption increase for the variable-charge soils than permanent-charge soils. When tartrate and Cd solution were added together, sorption of Cd decreased with tartrate concentration for the yellow-brown soil, but increased at low tartrate concentrations and then decreased with tartrate concentration for the red soil and the latosol. |
| Key Words: cadmium sorption, organic acids, variable- and permanent-charge soils |
| Citation: Hu, H. Q., Liu, H. L., He, J. Z. and Huang, Q. Y. 2007. Effect of selected organic acids on cadmium sorption by variable- and permanent-charge soils. Pedosphere. 17(1): 117-123. |
| |
|
View Full Text
|
|
|
|
